Process of separating substances of different dielectric capacities.



No. 813,063. PATENTED FEB. 20; 1906. H. SUTTON & W. L. & E. G. STEELE. PROCESS OF SEPARATING SUBSTANCES OF DIFFERENT DIELECTRIC CAPACITIES.

' APPLICATION FILED APR.1B. 1903- m My 5 BY E 06.5

Hfzomey [UNITED sTATEs PATENT oEEIoE.

- HENRY M. SUTTON, WALTER L. STEELE AND EDWIN e. STEELE, or

' DALLASKJPEXAS.

PRdCESS F SEPARATING SUBSTANCES OF DIFFERENT DIELECTRIC CAPACITIES.

Specification of Letters Patent.

Patented Feb. 20, 1906.

Application filed April 18. 1903. Serial No. 153,305.-

provements in Processes of Separating Substances of Different Dielectric Capacities, of

which the following is a specification, refer ence being had therein to the accompanying drawin I This mventionrelates to an electrical process of separating the particles of a mass or the particles or substances and also by magnetic or diamagnetic efiects produced upon a limited number of certain substances intro duced into the field of an electromagnet eX- cited by an alternating current, the diamagnetic particles tending to move from the strongestto the weaker part of said field, the

maximum effect manifesting itself in particles which are conductors of electricity.

' One of the principal objects and advantages of our invention is to provide an electrical process/of separation which can be applied to substances re ardless of their being for not being electrical conductive or magnetic; v

Our invention, briefly stated, consists in developing insth'e particles or components to be separated dielectric hysteretic lmpedance.

. Our lnvention also consists invarious modifications in the degree, periodicity, and maintenance of said impedance, 'as will hereinafter be more fully set forth.

Dielectric hysteretic, impedance may be produced from various sources of ene and y various manners of and means for applying the same. In the present instance We em 10y an alternating, varying, or it may be a p ating statlc current to produce dielectric ysteresls' in the substances. we desire to separate, and this dielectric hysteresis im- I pede's the static charges on the surface of the particles of the mixture and is What we have denominated dielectric hysteretic impedance, the overning factor in our ieces-smite pro uced bystatic' currents .that alternate' in polarity, making an alterfiating'static field, or by static charges which are pulsating, but of the same polarity, making apulsating. static field, or by static charges which vary strength, making a static field of varying intensit or by alternating static currents of unequa periods, the positive polarity being of longer duration than the negative, or vice versa, or of greater strength than the negative, or vice versa, .or the said impedance maybe produced'by any one of the above-mentioned types of currents or by a combined or simultaneous use of any one or more of them and variation of a static'current will produce dielectric hysteresis; but

com onents of a nuxture or of material in I the latter seems more marked in an alternat- 'soli (pulverized,) liquid,'or gaseous form.

ing static current, and we have discovered that certain substances respond to a given periodicitymore readily than others, the range observed, though not to be taken as a limitation of our invention, being from two to twenty-five alternations per second. The development of a suflicient dielectric hysteretic impedance to cause particles to be swerved one direction than th other, so that changes in polaritylfof the static field and of "periodicity have efiective value. in developing 1n the particles the desired hysteresis. When subjected to periodic, pulsating, or varied electrostatic influence or stress, particles take on a molecular strain or polarization, Which manifests itself after the removal of theyin: fluence or charge that causes strain, and its effectsare afterward shown by the appearance of'aresidual charge similar in its nature to that appearing in a Leyden jariafter'a few moments restsubse'quent-toa recent discharge. This residual charge varies in 'amount according to the dielectric which sepa'rates the two coatings of the jar. Similar conditions can be-brought about in our invention, the substances to'be separated bemolecules more easily turn on their aXisin ing the dielectric between the surfaces that:

or forces.

serve as media for the subjection of the substances to the action of the separative force While we do not limit our invention to any particular apparatus for practicing the same, reference is had to the accompanying draw ings as showin some of the many forms of apparatus whic may be utilized.

Figure I is 'a diagram of an apparatus adapted to subject material for separation to an alternating electrostatic field. Fig.2 shows means for varying the periodicity of the alternations. Fig. 3 shows means for varying the relative strength of the fields. Fig. 4 shows means for producing a pulsating field; Fig. 5, a modification of the apparatus shown in Fig. 1, and Fig. 6 is a diagrammatic illustration of means for varying the alternating current both in periodicity and potential.

- Like letters of reference refer to like parts in the several figures of the drawings.

In Fig. l, A is a hopper provided at its outlet with a shaking pan A, operated by an eccentric A and connecting-rod A to distribute the mass coming from the hopper upon the cylinder B, which is provided with any suitable means for rotating in the direction indicated by the curved-arrow. The cylinder B has an insulating-covering B and an outer conducting-surface B, which is adapted to be charged by a brush B connected by electrical conductors-C, C, and C with an al-- ternating static generator or pole-changer D.

At one side of the cylinder B a metallic plate I or screen E is located, and this may be whereby charges of successive signs, plus and minus, will pass throu h said holes to one of the terminals C orv C urin each revolution of the disk. A given spec of rotation will. deliver a definite number of positive and a definite number ofnegative charges to the cylinder B, whereby any desired frequency" canbe attained. To vary the relative perio-' dicity ofalternation, a slot 'D Fig. 2 may be usedinstead of a-hole D in any series of open-' ings which may be formed in the disk D, as above stated. x F andF represent connections, Ins and minus, with any desired source 0 energy, preferably a. static generator.

G is a receptacle having compartments G and G for separated partlcles and a pivoted gate G on the partition G The operatlon in the form shown in Fig. 1

is as follows: The mass is fed from the hopper to the conductin -surface of the cylinder, which is charged froman alternating source of static electricity capable of giving definite periods of alternations. Some of the particles of the mass thus subjected to periodic changes are caused-to differ in potential from that of the surface of the cylinder, while others that develop little hysteretic impedance at certain periodicities of the electrostatic charges are practically capable of allowing the charges induced on their surfaces to follow in'phase that of the conveying-surface of the cylinder, so that an alternation of one polarity practically-neutralizes that of the other,

and these particles consequently remain in an approximately neutral condition, and on rotation of the cylinder they drop through the screen into the compartment .G of the receptacle G. On the contrary, the particles which by impedance in phase caused by their molecular polarity or hysteresis lag in phase of change behind that of the conducting-surface, and this causes a difierence of potential to be constantly maintained between the particles and the conductin -surface. B of the-cylinder, so that they a here until further rotation of the cylinder carries them beyond the condensing action of the screen E, and they fall into the compartment G of the receptacle G. Theiscreen E serves to bring about the opposite relation of the conducting-surfaceB so as to intensify the electrostatic field of the same. v

Fig. 3 shows one means of applying our process to those classes of substances which i show preference for the different signs of electrification, which means is adapted to deliver to the conducting-surface B static charges of unequal strength. This can be done by varied means. In this instance the condensers H H of relatively unequal capacity are placed in the branches C and C the former leading to the surface B the latter to the screen E, or it may be vice versa.

Fig. 4 shows one means for applying pulsating char es to the surface B, said means involving t use of Leyden jars I I in the connections C and C, leading to the screen E and surface 13. F and F are the terminals of a static generator which has suitable knobs I I .so that by adjusting these knobs sufficiently close the dischargewhich takes place across the air-gap causes electrical oscillations at the connections C and Cv and in the screen and the conducting-surface. In these cases the frequency of the discharges may be regulated by adjusting the sizes of the condensers or Leyden jars, adjustin 'the air-ga oil providing the condensers wit adjustable ates.

p In Fig. 5 a late E is substituted for the c 'linder B, w 'le the material is allowed to fall by gravity between said lateand a screen or plate E grounded at whereby in separate receptacles.

Fig. 6 illustrates a form of the invention wherein a current from the generator through coimections F F of Fig. 1 may be alternated by' the insulating-disk D, ivoted-at D and provided with a slot D an such alternation varied in periodicity by a hole D in the disk in. connection with the slot D. In this instance the alternation would possess successive lon g and 51101 t periods, the former throu h the slot and the latter through the ho e. The alternating current thus varied may be further varied 1n its potential by condensers H H of relatively unequal capacity laced in circuit with the conductors C C, y which successive alternations over the conductors C to the screen E of Fig. 1 differ in otential, thus causing both alternations an variable intensity in the field In all the forms of apparatus herein shown no dependence is required upon the specific gravity, electrical conductivity or non-conductivity of the particles of a mass, all of which in actual practlce are so slight as to render practical separation'difiicult but by-using our process the substances are exposed to' an electrostatic field of a pulsating or an alternating or of a varying potential, the alternations, variations, or pulsatior-s being so timed as to cause and maintain a difference of potential between certain substances in the mass in or on surfaces that they are in contact with or adjacent to. The actual and practically-demonstrated separation is effected by taking advantage of the effects of dielectric hysteresis set up in the different particles in the mass when it is exposed to stresses of an alternating or y arying electrostatic field. The result of developirg in the particles of the mass dielectric hysteresis is to counteract in part the true char e induced on their surfaces, so as to cause t em to carry a charge of a different value to that of a conveying (or of an influencing) surface on which (or near which) they travel, while those particles .whose hysteretic impedance is not so sufficiently manifested at certain periodicities or alternations or pulsations practically follow the phase of the conductir g-surface so that charges of opposite signs follow each other on the surfaces of such particles and cause them to ractically remain in a neutral condition,- w ich facil i' tates subsequent actual or mechanical separation.

In our developmer t .of this invention it has been discovered that when the inductive member-forinstar.ce, the screen E in Fig.

'1is.charged at a constant static potential intead of an alternatingpotential, while the conducting-surface for instance, at B in Fig. 1is charged with an alternating, pulsating, or varying potential static current or charges, as we have previously described, the eflicienc of the process is very greatly increase .This is due to a state of tension in which the molecules are laced by the continuous static charge, whic renders them more responsive to the" alternating static charges, and thus comprises a simple and efficient manner of increasing the sensitiveness of substances to electrostatic charges or impulses. The screenor inductive member may be connected with one side of an electrostatic generator, as shown in Fig. 1 at E or may be grounded, as at E in Fig. 5.

.Variouschanges. and modifications may be made in the manner of applying our process in actual ractice and use. Therefore we do not hunt the same to those hereinbefore shown and described, but apprehend any such as of our invention when such changes adopted are within the expected skill of persons conversant with the electrical principles involved. For example, in subjecting materials to the action of varied electrostatic charges for the purpose of separation said variations may be in degree or intensity, potential, polarity period of maintenance, periodicity or rapidity of altemation, and each of these may be inco'ziju'ziction with char "ges of polarity for equal or unequal periods and of equal or unequal strength, the positive or negative being the stronger, and by employing simultaneous or successive alternating and pulsating static currents and by other variations which will induce or develop dielectric hysteretic impedance.

The term "dielectric hysteretic impedance as hereinafter used is what may be termed a lag of charge in dielectrics under the influence of alternatir. or irregular stress produced fromany desire source of energy. The lag of charge results in maintaining a difrerence of potential in or on the'particles.

Having described our invention and set forth its merits, what we claim, and desire to. secure by Letters Patent, is

1. In a process of separating the particles of a mass or the components of a mixture, developing in said particles or components dielectric hysteretic impedance, and separately collecting the particles.

In a process of separation, subjecting a mass or mixture to the action of a varied static charge 3130 establish dielectric hysteretic impedance and separately collecting the I components.

3. In a process of separation, subjecting material to be separated to the action of alternating and varied electrostatic charges to establish dielectric hysteretic impedance, and separately collecting the separated components of the material. I

4. In .a process of separation, subjecting material toalternating electrostatic charges of unequal periodicity to establish dielectric hysteretic impedance, and separately collect ing the separated components.

5. In a process of separation, subjectingmaterial to the action of electrostatic charges in periods adapted in rapidity to establish dielectric hysteretic impedance in any particular material being separated, and separately collecting the separated components.

6. In a process of separation, subjecting material to the action of electrostatic charges varied in periods, potential and in polarity in accordance with the preference-of the material being separated to establish dielectric hysteretic impedance, and separately collecting the separated components.

7. In a process of separation, subjecting material to the action of alternating electrostatic charges varied in potential to establish dielectric hysteretic impedance, and separately collecting the separated components.

8. In a process of separation, subjecting material to the action of electrostatic charges varied in the potential of their opposite signs to establish dielectric hysteretic impedance, and separately collecting the separated components.

9; In a process of separation, subjecting material to the action of electrostatic charges varying in the duration of their opposite signs to establish'dielectric hysteretic impedance, and separately collecting the separated components.

10. In arprocess of separation, subjecting material to the action of electrostatic charges varying in the duration and potential of their opposite signs to establish dielectric hysteretic impedance, and separately collecting the separated components.

i '11. In a process of separation, subjecting particles of a mass or com onents of a mixture to the action'of an a ternating electrostatic charge to establish dielectric hysteretic impedance, and,separately collecting the sep arated components.

' 12. In a. process of separating particles of a mass'or components of a mixture, developing in said particles or components dielectric hysteretic impedance and simultaneously exposing. them to the inductive action of a polariz'ed terminal, and separately collecting the separatedparticles or components.

13. In a process of separation, passing'material through a field having at one point an alternating static charge and at an opposite point aconstant static charge to established electric hysteretic impedance, and separately collecting the separated components.

14. The process of separation which consists in subjecting material to the action of an alternating varied electric field of force capable of maintaining a difference of potential .to establish dielectric hysteretic impedance,

removing from the said field by an auxiliary force such particles as are electrified, and separately collecting the separated components.

16. The process of separation which consists in constantly charging a mass or mixture to be separated with a varied and alternating potential to establish dielectric hysteretic impedance, feeding the mass into a dielectric medium and removing therefrom such particles as differ in their electrical relation thereto. and separatelycollecting the separated components.

17. The process of separating particles of a mass or components of a mixture which consists in charging the same with an electrostatic current of varied potential to establish dielectric hysteretic impedance. simultaneously exposing the same to the inductive action-of a polarized terminal, and collecting separately the particles which are sufliciently responsive.

18. In a process of separating the particles of a mass or the components of a mixture producing therein a/lag of charge on said particles or components, and separately collecting the separated particles or components.-

19. The process of subjecting the particles of a mass or the components of a mixture to the action of an electrostatic current of varying potential so as to cause and maintain a difierence of'potentialbetween the particles, simultaneously exposing the same to the inductive action of a polarized terminal, and separately collecting the particles that are sufiiciently responsive.

20. In a process of separation, subjecting a mass or mixture to the action of a varied static charge regulated to effect a separation by its action upon the dielectric capacity of the particles and separately collecting the components.

In testimony whereof we aflix our sign'a tures in presence of two witnesses.

HENRY M. SUTTON.

WALTER L.-STEELE. EDWIN e. STEELE.

Witnesses v GEO. W. J ALOWICK, EMMA OURTnIoHT. 

